Air supply device for internal combustion engines



Nov.- 17, 1936. F. MUELLER 2 AIR SUPPLY DEVICE FOR INTERNAL COMBUSTIONENGINES Filed June 17, 1955 2 Sheets-Sheet 1 NOV. 17, 1936. MUELLER2,061,166

AIR SUPPLY DEVICE FOR INTERNAL COMBUSTION ENGINES Filed June 1'7, 1935 2Sheets-Sheet 2 Patented Nov. 17, 1936 UNITED STATES AIR SUPPLY DEVICEFOR INTERNAL COIVLBUSTION ENGINES Frank Mueller, Scranton, Pa., assignorof onethird to J. R. Cadoret and one-third to M. B. Comerford, both ofScranton, Pa.

Application June 17, 1935, Serial No. 27,092

19 Claims.

This invention relates to a mechanism for introducing a supply of air tothe fuel line of an internal combustion engine.

One object of the invention is to provide means whereby the amount ofair which is supplied to the fuel line is automatically controlled inaccordance with the requirements of the engine under various operatingconditions, and to secure maximum economy and efiiciency of operation,

Another object is to provide means for adjust-- ing the automaticcontrol in accordance with the peculiar requirements of any individualinternal combustion engine and the use to which the engine is placed.

Another object is to provide means for efficiently mixing the air, whichis thus introduced, with the fuel.

A further object is to provide a mechanism which will be rugged anddurable and which, in its preferred embodiment, may comprise a unitadapted to be secured between the conventional carburetor and intakemanifold of an automobile, although the structure of the invention maybe incorporated directly in a carburetor or other fuel supply means.

Other objects and advantages will beapparent from the followingdescription.

Referring to the accompanying drawings,

Figure 1 is a vertical section on the line II of Figure 2.

Figure 2 is a horizontal section on the line 2-2 of Figure 1.

Figure 3 is a transverse section on the line 3-3 of Figure 2.

Figure 4 is a vertical section similar to that shown in Figure 1, butwith the parts in a diiferent position, and

Figure 5 is a plan view of a modified form of the invention.

The invention preferably takes the form of a unitary body or memberwhich may readily be incorporated in the conventional assembly of acarburetor and intake manifold without requiring the attachment ofpartsto the carburetor mechanism or other control mechanism of theengine. In its preferred embodiment the invention consists ofasubstantially flat body'or casing member which may be inserted betweenthe carburetor and intake manifold without other connections than thebolts which are usually employed to assemble these parts. In thedrawings, the numeral I indicates a member, having a central aperture 2,adapted to be secured between the usual intake manifold flange 3 and theopposed flange 4 of the carburetor outlet pipe 5. Bolts 6 passingthrough appropriate apertures in the flanges and the member I hold theparts in position.

The member I is provided with an air inlet in the form of one or moreair ports I, 'I, which extend inwardly from one side and open into atransverse concavity 8 communicating with a channel 9 extending aroundthe circumference of the aperture '2. The channel 9 is preferablycovered by a wire screen I0, which may be made of bronze wire.

The air inlet is valve controlled and, in the embodiment illustrated,each of the air ports I, I, is provided with an air valve comprising acap I I and a tubular body member I2 having a transverse partition I3provided with apertures I4. The body I2 is provided at its outer endwith a skirt I5, the edge of which forms a seat for the cap I'I. At itsinner end the body is provided with a hollow screw threaded extension I6which is screwed into the port I, the latter being provided with asuitable internal screw thread. 'By turning the body I2 the air valvemay thus be moved toward or away from the member I for a purpose whichwill presently appear. A lock nut I1 is threaded on the extension I6 andserves to maintain the valve in any desired position.

A stem I8 is rigidly secured at the center of each of the valve caps II,II, and extends inwardly through a central aperture in the partition I3of the body I2, terminating in a shoe I9. A helical expansion spring 20encircles the stem I8, one end bearing on the shoe I9 and the other endbearing on the transverse apertured partition I3. The spring 20 thusurges the shoe I9 inwardly and hence causes the valve cap II, with whichthe shoe is connected by the stem I8, to seat tightly against the end ofthe skirt I5 to seal the port I.

A rocker arm 2| is secured to a rock shaft 22 which is pivotally mountedin the transverse concavity 8. The rock shaft 22, extending transverselywith respect to the ports I, I, has a substantially fiat upstanding rearportion 23 which normally lies in close proximity to, or contacts, thevalve shoes I9, I9.

As will be seen from an inspection of Figure 1, upward movement of therocker arm 2I will rotate the rock shaft and cause the upstanding rearportion 23 to move outwardly in an arc, pushing the valve shoes I9, I9outwardly to open the air valves.

The rocker arm 2| is so arranged that it projects into the interior ofthe intake passage and, as shown in Figure 1, its end may projectdownwardly into the carburetor outlet pipe when in Its lowermostposition.

A conventional butterfly throttle valve 24 is disposed in the carburetoroutlet pipe 5 in the usual manner and in such a position that when itmoves from closed toward open position its edge contacts and raises therocker arm 2 I.

The rocker arm 2I is preferably provided on its underside with a camsurface consisting of a rise 25 and a dwell 26 so that as the butterfly24 is moved from closed to intermediate position,

the upward movement of the rocker arm will be accentuated as the edge ofthe butterfly passes over the rise 25, and as the butterfly moves fromintermediate to wide open position its edge passes into the dwell 26 andthe rocker arm is thereby permitted to drop. It will be apparenttherefore that by reason of the formation of the rocker arm so as toprovide the cam surface, movement of the throttle valve toward openposition imparts a variable movement to the air valve. That is to say,the opening movement of the air valve is not directly proportional tothe opening of the throttle valve, but varies in accordance with the camformation.

It will be apparent that when the rocker arm is in its lowermostposition and one of the valves is so adjusted that its shoe i9 is inclose proximity to the rock shaft as shown in Figure 1, or barelycontacts the rock shaft, the air valve will be held in closed positionby the spring 20. With the air valve so adjusted and the throttle valvein closed position, or only slightly open aswhen the engine is idling,no air will be admitted through the air port I and the mixture whichpasses to the engine will be rich in fuel. As the engine speed isincreased by opening the throttle valve the rocker arm will be raisedand the air valve will be gradually opened, as explained above, in orderthat a supply of air may be drawn into the intake passage, by thesuction therein, through the air port. The rate at which the air valvewill be opened as the throttle is opened will depend upon theinclination of the rise 25 which is preferably designed so that the airValve will be fully open when the throttle valve is about halfway open.In other words, when the car is travelling at approximately half speedthe maximum amount of air enters through the port 1, resulting in amaximum economy of fuel consumption.

As more power is required and the throttle valve is moved fromintermediate to fully open position, it is desirable to reduce graduallythe supplyof air which is admitted through the port I and, as explainedabove, the rocker arm will fall and the air valve will be graduallyclosed as the throttle valve is moved toward fully open position owingto the provision of the dwell 26 next to the rise 25. The rate at whichthe air valve will close as the throttle is so advanced will depend onthe angle of incline of the cam surface between the rise and the dwell.It will be seen that when the maximum amount of power is required andthe throttle valve is fully opened, the mixture which passes to theengine will be rich in fuel.

Where two air ports are provided, the two air valves may be so adjustedthat they will operate as described above, but it is frequently desiredso to adjust the two air valves that one will open before the other andclose before the other, so that the amount of air which is admitted willbe varied more gradually. To do this, it is only necessary to adjust therespective air valves as shown in Figure 2, where, when the rocker armis in its lowermost position, the shoe I9 of one alve is in closeproximity to the rock shaft, while the other valve is screwed out sothat its shoe is farther away from the rock shaft. With such anadjustment it will be seen that upon opening the throttle valve, oneshoe will be contacted by the rock shaft and moved rearwardly before theother and hence the corresponding air valve will be opened before theother. When the throttle valve is opened to an approximatelyintermediate position, both shoes will have been pushed rear-- Wardlyand hence both valves will be opened. As the throttle valve is furtheropened one shoe will arrive at its innermost position before the otherand hence its corresponding valve will be closed first.

It will be apparent that both of the air valves may be adjusted to thesame position so that neither will be affected until the throttle hasreached an intermediate position.

Furthermore, it is possible, and in certain cases it may be desirable,to position one of the valves so far outwardly with respect to member Ithat its shoe cannot be contacted by the portion 23 of the rock shaft,with the result that the valve will remain closed at all times. It mayalso be desired to move one valve so far inwardly that its shoe isconstantly being held out by the rock shaft or its upstanding rearportion so that the valve will be open at all times.

It has been found that with some engines it is desirable that the airvalve, or valves, be closed during idling, wide open at half throttle,and partially but not entirely closed at full throttle. This result maybe achieved by making the dwell on the cam surface of the rocker armsomewhat shallower. Likewise, it will be found desirable to change thespecific form of the throttle valve contacting surface of the rocker armfrom that shown in the drawings, to suit various types of carburetorsand engines.

It will be desirable in some cases to use one air port and in othercases two or more air ports may be preferable.

As shown in Figure 5, the invention is applicable to that type of enginewhich uses a plurality of carburetors and a corresponding number ofbutterfly throttle valves. One air port and air valve may be providedfor each of the butterfly valves, which, as shown, may be arranged on acommon shaft.

As set forth above, the upward movement of the rocker arm 2! will rotatethe rock shaft 22, causing the upstanding rear portion 23 of the rockerarm to push the valve shoes l9, l9 outwardly to open the air valves.

The springs 28, 20, urging the valve shoes inwardly, oppose upwardmovement of the rocker arm and cause it to remain in its lowermostposition when the butterfly throttle valve is fully closed or fullyopen. It is desirable that the springs be light enough so that they willnot interfere with the ordinary operation of the butterfiy valve and yetbe heavy enough to maintain the rocker arm in its lowermost positionwhen the throttle valve is closed.

The above described channel 9 into which the air passes after comingthrough the ports i, l, is of great importance in securing an efiicientand even mixture of the gases. Part of the air passes directly from theconcavity 8 into the intake passage, but a considerable part of the airis dividedinto diverging streams which flow into the circumferentialchannel 9, and around the aperture 2 in opposite directions to meet onthe other side. This construction results in an even mixture of the airand fuel, because the air is drawn from all parts of the channel by thesuction in the intake passage and enters the stream of gaseous fuel fromall directions.

The wire screen I!) assists this flow of air into and around the channel9 and, since it becomes very hot when the engine is running, it causesan appreciable preheating of the gases flowing through the intakepassage.

It will be seen'that the invention, in its preferred embodiments,mayreadily be attached between the conventional carburetor andmanifoldof an internal combustion engine by an unskilled person, since noadditional attachments or adjustable devices need be used in connectionwith it.

While the invention has beendescribed as an attachment adapted to beused in connection with conventional gasoline engines andcarburetors;the inventive concept is not so limited, since thecombination of elements incorporated may be directly in a carburetor orother fuel supply means.

I claim:

'1. An attachment for an internal combustion engine having a throttlevalve, comprising a-rnemher having a central aperture and adapted to besecured between the intake manifold and the fuel supply of the internalcombustion engine, the member being provided with a port through whichair may be drawn into the intake manifold, a valve mounted in saidmember and controlling the passage of air through the port, and an armpivotally mounted in said member independently of said air valve andprojecting into said aperture, said arm being adapted to be contactedand moved by the throttle valve and being operatively associated withsaid air valve whereby to actuate the latter.

2. An attachment for an internal combustion engine having a throttlevalve, comprising a member having a central aperture and adapted to besecured between the intake manifold and the fuel supply of the internalcombustion engine, the member being provided with a port through whichair may be drawn into the intake manifold, a valve mounted in saidmember and controlling the passage of air through the port, and a levermounted independently of said air valve in said member and operativelyassociated with the air valve to actuate the same, said lever projectinginto said aperture and being arranged to be contacted and moved by thethrottle valve.

3. An attachmentfor an internal combustion engine having a throttlevalve, comprising a member having a central aperture and adapted to besecured between the intake manifold and the fuel supply of the internalcombustion engine, the member being provided with a port through whichair may be drawn into the intake manifold, a valve adjustably mounted insaid member and controlling the passage of air through the port, and apivoted rocker mounted in said member independently of the air valve andadapted to operate the air valve, one end of said rocker being adaptedto be contacted and moved by the throttle valve.

4. An attachment for an internal combustion engine having a throttlevalve, comprising a member having a central aperture and adapted to besecured between the intake manifold and the fuel supply of the internalcombustion engine, the member being provided with a port through whichair may be drawn into the intake manifold, a valve controlling thepassage of air through the port, and a pivoted rocker arm, adapted tooperate the air valve, one end of which is adapted to be contacted andmoved by the throttle valve, the valvecontacting portion of the armbeing so formed that during only part of the movement of the throttlevalve toward open position the air valve is actuated toward openposition.

5. An attachment for an internal combustion engine having a throttlevalve, comprising a memher having a central aperture and adapted to besecured between the intake manifold and the fuel supply of the internalcombustion engine, the

member being provided with a port through which air may be drawn intothe intake manifold, a valve controlling the passage of air through theport, and a pivoted rocker arm, adapted to operate the airlvalve, oneend of which is adapted to be contacted and moved by the throttle valve,the arm being so formed at its portion which contacts the throttle valvethat during movement of the throttle valve toward open position the airvalve is opened, and :during further movement of the throttle valvetoward open position the air valve may close.

6. Anattachment for an internal combustion engine having a throttlevalve, comprising a member'having a central aperture and adapted to besecured between the intake manifold and the fuel supply of the internalcombustion engine, the member being provided with a port through whichair may be drawn into the intake manifold, a valve controlling thepassage of air through the port, and a pivoted rocker arm, which isadapted to operate the air valve, one end of which is adapted to becontacted and moved by the throttle valve, the throttle valve contactingportion of the arm being so formed that when the throttle valve is insubstantially wide open position and when it is in substantially closedposition the air valve is closed, and when the throttle valve is movedto intermediate positions the arm opens the air valve.

7. An attachment for an internal combustion engine having a throttlevalve, comprising a member having a central aperture and adapted to besecured between the intake manifold and the fuel supply of the internalcombustion engine, the

memberbeing provided with a plurality of ports 35 through which air maybe drawn into the intake manifold, a plurality of valves controlling thepassage of air through the ports, means operatively connected to eachair valve, and a rocker arm one end of which is adapted to be contactedand moved by the throttle valve and the other end of which is adapted toengage said means to operate the air valves, each of said means beingseparately adjustable with respect to the-rocker arm.

.8. An attachment for an internal combustion' engine having a throttlevalve, comprising a member having a central aperture and adapted to besecured between the intake manifold and the fuel supply of the internalcombustion engine, the member being provided with a port through whichair may be drawn into the intake manifold, a valve controlling thepassage of air through the port, and a cam operatively associated withthe air valve and adapted to be contacted and moved by the throttlevalve, said cam being provided with a rise and a dwell.

9. An attachment for an internal combustion engine having a throttlevalve, comprising a mem ber having a central aperture and adapted to besecured between the intake manifold and the fuel supply of the internalcombustion engine, the member being provided with a port through whichair may be drawn into the intake manifold, a valve controlling thepassage of air through the port, and means for operating said lastmentioned valve in accordance with movement of the throttle valve, saidmeans comprising an element mounted in said member and projecting intosaid aperture to be contacted by the throttle valve in its openingmovement, the element being arranged to impart a variable movement tothe air valve in the opening movement of the throttle valve.

10. An attachment for an internal combustion engine having a throttlevalve, comprising a member having a central aperture and adapted to besecured between the intake manifold and the fuel supply of the internalcombustion engine, the member being provided with a port through whichair may be drawn into the intake manifold, a valve controlling thepassage of air through the port, a cam operatively associated with theair valve and adapted to be contacted and moved by the throttle valve, achannel communicating with the air port and arranged circumferentiallywith respect to said aperture, and a perforated member covering saidchannel.

11. An attachment for the carburetor of an internal combustion enginecomprising a body having a central opening extending transverselytherethrough and adapted to register with the intake passages of thecarburetor and manifold, said body having a circumferential channelextending around said opening and an air inlet ,passage communicatingwith said channel, an

air valve in said passage, and means engageable with the butterfly valveof the carburetor to actuate said valve, said means being arranged toimpart a variable movement to the air valve in the opening movement ofthe butterfly valve.

12. An attachment for the carburetor of an internal combustion enginecomprising a body having a central opening extending transverselytherethrough and adapted to register with the intake passages of thecarburetor and manifold, said body having a circumferential channelextending around said opening and an air inlet passage communicatingwith said channel, an air valve in said passage, and means engage-ablewith the butterfly valve of the carburetor to actuate said valve, saidlast-mentioned means comprising a movable arm having a cam-shaped fingerportion adapted to bear on a butterfly valve whereby movement of thebutterfly valve actuates the air valve in accordance with the slope ofthe cam.

13. An attachment for the carburetor of an intern-a1 combustion engineadapted to be inserted between the carburetor and intake manifold and tobe clamped therebetween, comprising a body having a central openingextending transversely therethrough and adapted to register with theintake passages of the carburetor andrmanifold, said body having acircumferential channel extending around said opening and an air inletpassage communicating with said channel, an air valve in said passage,and means engageable with the butterfly valve of the carburetor toactuate said valve, said means being arranged to impart a variablemovement to the air valve in the opening movement of the butterflyvalve.

14. An air supply attachment for the carburetor of an internalcombustion engine comprising a body adapted to be clamped between thecarburetor and the intake manifold, an air passage in said body, a valvefor controlling said air passage. and means in. sliding contact with theedge of the butterfly valve of the carburetor to control said air valvein accordance with movement of the butterfly valve, said air valve beingadapted to permit the entry of additional air in accordance withmovement of the butterfly valve without other attachment to the movingparts of the carburetor.

15. In an internal combustion engine having a throttle valve, thecombination of a member having a central aperture and adapted to besecured between the intake manifold and the fuel supply of the internalcombustion engine, the member being provided with a port through whichair may be drawn into the intake manifold, a valve controlling thepassage of air through the port, and a lever operatively associated withthe air valve and adapted to be contacted and moved by a throttle valve,said lever having a cam portion for contact with the throttle valvewhereby to impart a variable movement to the air valve in the openingmovement of the throttle Valve.

16. In an internal combustion engine having a throttle valve, thecombination of a member having a central aperture and adapted to besecured between the intake manifold and the fuel supply of the internalcombustion engine, the member being provided with a port through whichair may be drawn into the intake manifold, a valve controlling thepassage of air through the port, and

a pivoted rocker mounted in said member adapted to operate the air valveone end of which is adapted to be contacted and moved by a tiltable inga central aperture and adapted to be secured between the intake manifoldand the fuel supply of the internal combustion engine, the member beingprovided with a port through which air may be drawn into the intakemanifold, a valve controlling the passage of air through the port, and apivoted rocker arm adapted to operate the air valve one end of which isadapted to be contacted and moved by a throttle valve, the arm being soformed that during only part of the movement of the throttle valvetoward open position the air valve is actuated toward open position.

18. In an internal combustion engine having a throttle valve, thecombination of a member having a central aperture and adapted to besecured between the intake manifold and the fuel supply of the internalcombustion engine, the member being provided with a port through whichair may be drawn into the intake manifold, a valve mounted in saidmember and controlling the passage of air through the port, and apivoted rocker arm mounted in said member independently of said valvemounting and adapted to operate the air valve, said rocker arm beingadapted to be contacted and moved by a throttle valve and being soarranged that during movement of the throttle valve toward open positionthe air valve is opened, and during further movement of the throttlevalve toward open position the air valve may close.

19. An attachment for an internal combustion engine having a throttlevalve, comprising a member having a central aperture and adapted to besecured between the intake manifold and the fuel supply of the internalcombustion engine, the member being provided with a port through whichair may be drawn into the intake manifold, a valve controlling thepassage of air through the port, means operatively connected to the airvalve, and a rocker arm, one end of which is adapted to be contacted andmoved by the throttle valve and the other end of which is adapted toengage said means to operate the air valve, the means being adjustablewith respect to the rocker arm.

FRANK MUELLER.

